Path Constraint deforming Mesh
for stability I don't allow bones to follow paths.  Instead I use an 'Empty' or dummy invisible 2D plane and parent the main armature to that, then have the dummy follow the path.  You could try that.

It's an easy matter to vary the main armature's attitude/rotation/pitch etc without having to worry about any interaction the path constraint might have.  I don't recall ever having problems varying individual bone movements either.